1. Field of the Invention
This invention relates to a process for the manufacture of .beta.-(dimethylamino)-propionitrile by reaction of acrylonitrile and dimethylamine. More especially, this invention relates to a process for reacting acrylonitrile and dimethylamine at mild reaction conditions in counter-current flow in a bubble column to obtain virtually quantitative yields of .beta.-(dimethylamino)-propionitrile.
2. Discussion of the Prior Art
The manufacture of .beta.-(dimethylamino)-propionitrile usually occurs via the addition of dimethylamine to acrylonitrile, corresponding to the following equation: ##STR1##
According to the JA Patent Application No. 72/03 809, gaseous dimethylamine is fed into acrylonitrile between 0.degree. and 5.degree. C. The reaction mixture is subsequently allowed to stand for one hour. .beta.-(dimethylamino)-propionitrile is thereby obtained in 99 percent yield.
The disadvantage of this process lies in the necessity of maintaining the temperature between 0.degree. and 5.degree. C. This is very involved technically--making the economic efficiency of this process questionable.
It is known from DL-P No. 58 306 that dimethylamine and acrylonitrile can be reacted, for example in co-current in a recycle apparatus at 0.degree. to 60.degree. C., using the reaction product as solvent and diluent. However, with this method, .beta.-(dimethylamino)-propionitrile is obtained in only a 94 percent yield.
It is an object of this invention, therefore, to provide a process for the manufacture of .beta.-(dimethylamino)-propionitrile whereby the product is obtained in a high yield using a simple apparatus and mild reaction conditions.